Goaltender Leland Irving, defenders Chris Breen, T.J. Brodie and Steve McCarthy and forwards Sven Baerts-chi, Paul Byron, Roman Horak and Ben Street are all in Calgary for the Flames training camp this week, which got underway Monday.
All eight players were absent for Tuesday and Wednesday's Heat games, and some may not return to Abbotsford again in their careers.
The transactions leave the Heat without four of their top five scorers, top offensive defenseman and the 'shutdown' pairing along the blue line.
Thirty-two players are attending Calgary's training camp with a maximum roster size of 23 players needing to be reached before the club's season opener next Sunday in Calgary against the San Jose Sharks.
Several players have been called up from the ECHL this week to join the Heat roster.
Defenders Mike Matzcak and Drew MacKenzie, as well as forward Mitch Wahl made their Heat season debuts in Saturday's 1-0 loss to the Chicago Wolves that saw the Heat outshoot the visitors 30-15.
Matczak and MacKenzie both manned a power play unit and played a regular shift, while Wahl played on the top line with Krys Kola-nos and Ben Walter drawing praise from coach Troy Ward in his post-game comments.
Wahl is in the final season of his entry level contract after being drafted by the Flames in the second round of 2008 NHL Draft, and was recalled by the Heat earlier in the week after amassing 39 points in just 30 games with the Utah Grizzlies (ECHL).
Mackenzie, a graduate of the University of Vermont, was participating in the first AHL game of his career on Saturday after starting his first pro season in Utah.
Matczak finished four seasons with Yale (ECAC) in 2010-11 and had played 11 AHL games in his career prior to his arrival in Abbotsford this week. The 24-year-old has been a member of the Kalamazoo Wings (ECHL) for the past two seasons.